Most of man's machines and electrical devices have controls of some type to regulate their functions. Such controls consist of such items as buttons, triggers, levers, dials, pedals, toggle sticks, etc. Many times prior art controls of the indicated type are actuated accidentally, with inconvenient and sometimes disastrous results. Examples include: pulling the trigger on a gun by mistake, turning on an electrical switch accidentally in cases where the switch operates a machine, or pressing the shutter release on a camera unintentionally.
Many methods have been employed in the past to prevent such accidents. With respect to guns, a safety lock has been provided, which must be released before the trigger can be pulled. In the case of electrical switches, two or more buttons or levers must be actuated before the current is turned on. Some switches are placed in hard-to-reach places, and some require a complex manipulation of the switch before it will perform its function. All of these prior methods have the drawback of requiring the user to expend extra effort or skill.
Further, none of the known methods work on what is the handiest, yet most infrequently used control. This is the proximity switch, i.e. the type that is triggered when a person or object comes close to it. Popular acceptance of this switch is severly limited by the fact that it can be easily triggered through inadvertence, this limitation making it impractical for many uses.
It is desirable, therefore, to have an apparatus and a method of preventing controls from being accidentally actuated.